Cartridge case



Nov. 29, 1966 H, STADLER ET AL 3,288,066

CARTRIDGE CASE Filed March 1o, 1964 2 sheets-sheet 1 A TTORN YS.

Nov. 29, 1966 Filed March lO, 1964 H. STADLER ET AL CARTRIDGE CASE 2 Sheets-Sheet 2 INVENTORS. 4HANS STADLER HEINZ GAWLICK BY UDOLF STAHLMANN A TTORNE United States Patent O 3,288,066 CARTRIDGE CASE Hans Stadler, Nurnberg, and Heinz Gawlick and Rudolf Stahlmann, Furth, Bavaria, Germany, assignors to Dynamit Nobel Aktiengesellschaft, Troisdorf, Germany Filed Mar. 10, 1964, Ser. No. 350,861 8 Claims. (Cl. 102-38) The present invention relates to a cartridge case, and more particularly to an improved plastic propellant charge container.

It is known in the prior art to shoot a fastening element, for example, a bolt provided with a thread, a nail or a dowel pin into a wall or to produce perforations or depressions by means of tools driven or actuated by powder force.

It is also known in the prior art to utilize, especially for blank cartridges, cartridge cases closed in front and made of elastic synthetic material which at the open end thereof on the side of the primer or detonator, are slipped form-lockingly and force-lockingly over the tubularly shaped extension of a metallic bottom piece, and in which the length of the inner cartridge case corresponds approximately to the length of the cartridge chamber of the firearm, and in the hollow spaced in which is contained the powder which is primed or ignited by means of a primer or percussion cap. The forward closure of the cartridge case is provided in these prior art structures with mutually crossing weakening lines along which the cartridge case walls burst and break open as a result of the gas pressure.

The present invention relates to a cartridge with a propellant charge accommodated within a plastic cartridge case or propellant charge container closed on the front thereof for an artillery-type projectile or for a projectiletype bolt which is to be used for technical purposes of the type mentioned hereinabove. The projectile or bolt may be adapted in a conventional manner, known per se, to the purposes which it is supposed to fulll. The present invention is primarily characterized by the fact that the gas pressure tears-off and breaks open the plastic cartridge case or propellant charge container at a predetermined place, for example, predetermined along the wall cross section thereof and lires or shoots the torn-off plastic cartridge case or container or the torn-open cartridge case together with the projectile out of the barrel thereof. It has been discovered thereby to be appropriate that the tearing-off takes place directly at the metallic primer support so that after the firing only the primer support together with the fired percussion cap or primer remain within the cartridge chamber whereas the projectiles or bolts are shot out of the barrel together practically with the entire plastic cartridge case or propellant charge container.

The propellant charge may consist of wound powder foil which is made in a manner, known per se, of nitrocellulose with the addition of a nitro-compound.

This propellant charge can be ignited by means of a rim primer means, central primer means or electric priming means, all of conventional well-known construction.

With a cartridgemade in accordance with the present invention either a plastic container for an ignition booster which extends into the propellant charge or a metallic sleeve with a plastic cap for the ignition booster is arranged at the bottom piece of the plastic cartridge case. The plastic booster case closed in front is then also secured at the rear end thereof with clamp or forcel t to the bottom piece by insertion of the rim into an overlapping internal flange provided in the ignition channel of ICC the Ibottom piece. The plastic cap of the ignition booster, in contrast thereto, is held by a clamp or force lit on a bead of the metallic sleeve.

The plastic cartridge case of the propellant charge is relatively thin-walled and is provided near the bottom piece with an externally and particularly also with an internally reinforced wall part. The forward end of the propellant charge container or cartridge case is constructed as forwardly open blank or cup, whereby the propellant charge space is closed by the bottom of the cup. l

The projectile can be held fast with a force or clamp lit by means of the side walls of the blank or cup.

The cartridge case can also be stored without projectile together with the primer and powder propellant charges because with the construction according to the present invention these materials are closed-olf on all sides even without the projectile. In case of an ignition caused by accidental circumstances, a larger damage cannot occur because a dangerous explosive pressure cannot develop due to the rapid tearing-off of the plastic cartridge case or propellant charge container.

The ignition in the cartridge ready for firing is initiated in a manner, known per se, either mechanically or electrically at the percussion cap or primer, disposed in the -bottom piece, by a conventional tiring mechanism whereupon the propellant charge is ignited either indirectly by way of the ignition booster in the plastic booster container or directly and the gas pressure thereof, depending on the construction of the plastic container or cartridge case tears-off only the forward part of the container or cartridge case together with the projectile or bolt or separate nearly the entire plastic container or cartridge case together with the projectile from the metallic bottom piece.

The tearing-off of the plastic container or cartridge case from the Abottom piece can be further aided in that the plastic container or cartridge case which contains the propellant charge is inserted into a hollow space of the projectile so that the projectile surrounds the plastic cartridge case or container so to speak. The walls of the surrounding hollow space of the projectile may reach up to the outer collar of the bottom piece. However, the outer collar of the bottom piece has to be larger than the caliber of the projectile in order that it holds stationary the thus constructed cartridge within the cartridge chamber. The plastic cartridge case is thereby provided in accordance with the present invention with an external bead arranged within the area of the bottom piece which fastens the projectile at the plastic container or cartridge case and reinforces the container or cartridge case walls, and an empty space is arranged in front of the relatively strong end wall thereof within the hollow projectile space.

There is achieved by the use of such a construction that the plastic propellant charge container or cartridge case tears-olf directly in front of the external bead.

Propellant charge containers or cartridge cases of this type may be utilized very advantageously also for launcher-type cartridges of a trench mortar. In that case, the propellant charge container or cartridge case is pressed or threaded into the t-ail piece of the grenade or Isihell. In the latter case the metallic bottom piece is provided with `a thread. The walls of the tail piece possess he usual lateral apertures for a radial gas discharge. Upon ignition of the propellant charge the gas pressure punches out or perforates in the plastic cartridge case, iholes or apertures corresponding to the lateral gas discharge apertures of the tail piece through which the propellant gas enters into the trendh mortar barrel which is closed-off in the upward direction by the grenade or projectile head. The propellant gases then act in known manner on the projectile or grenade head and propel the same out of the barrel. With such a cartridge the plastic cartridge case yor container is constructed according to the present invention shorter than the depth of the ihollow space of the tail piece. Accordingly, a certain empty space closed on all sides remains free in front of the plastic cartridge case or container. Upon the development of the gas pressure the iside walls of the plastic cartridge case are perforated lor punched-out at the perforation places of the tail piece as well as the forward end part of the plastic cartridge case is torn-off. The gas pressure thereby expands into the empty space. As a result thereof, the gas pressure peaks are reduced and the danger 'of exploding, cracking or bursting of the tail piece is avoided. Surprisingly it has been discovered that the power is in no way impaired by the tearing-off of the end wall of the plastic cartridge case or container'but instead only the gas pressure peaks are reduced and the propelling effect of the propellant gases is distributed over a longer time `span which has a favorable effect on the energy delivery. The construction is thereby made in such a manner that the end walls of the cartridge case or container tears-off sooner than the perforation of the :side Walls thereof. It is thereby -avoided that the cartridge case or container might still move after lthe perforation and thereby prevents the gas discharge. This, however, can be achieved only if the ignition booster coupled with that bottom piece which consists of oxygen carriers such as barium nitrate and metallic reduction agents such as aluminum, magnesium, zirconium, calcium silicate, is so strong that the time from ignition up to attaining the gas pressure peak lies within 'a millisecond. This is achieved according to the present invention in that the primer or detonator composition and the booster are combined `spatially close to each other in a compact manner `and together possess 3%-l0% of the weight of the powder charge.

Accordingly, it is an object of the present invention to provide a propellant charge container of the type described hereinabove which avoids the shortcomings and drawbacks encountered with the prior art constructions by simple 'and relatively inexpensive means.

Another object of the present invention resides in the provision of a cartridge case which is so constructed and arranged as to assure tearing-off of Ithe plastic cartridge case or propellant charge container in predetermined places, so that the torn-olf cartridge case is shot out of the barrel together with the projectile.

Another object of the present invention resides in the provision of a cartridge case made of plastic material which is so constructed that :after firing only the primer support together with the fired primer remain within the cartridge chamber while the propellant charge container or cartridge case is fired together with the projectile.

A further object of the present invention resides in the provision of a cartridge case which can be readily stored together with the ignition nad propellant charges, even in the absence of the projectile, without danger of harmful explosions caused by accidental ignition.

Still another object of the present invention resides in the provision of a cartridge case or container made of plastic material which limits the peak gas pressures as well as minimizes dangerous explosive pressures owing to the rapid tearing-olf of the plastic container or cartridge case.

Another object of the present invention resides in the provision of a propellant charge container or cartridge case made of plastic material which causes a reduction in the peak gas pressures without impairing the power of the charge and which favorably affects the energy delivery by extending the time period during which the propellant gases yare given off.

These and other objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein:

FIGURE l is an axial cross-sectional View, on an enlarged scale, of a cartridge provided with a cartridge case or propellant charge container according to the present invention and with a projectile constructed as pointed solid body and having central primer,

FIGURE 2 is an axial cross-sectional View through a modified embodiment of a cartridge having a propellant charge container or cartridge lcase in accordance with the present invention and provided with central primer and with a projectile constructed as threaded bolt,

FIGURE 3 is an axial cross-sectional view through still another modified embodiment of a cartridge case in accordance wtih the present invention over which is placed a projectile extension, and

FGURE 4 is a partial axial cross-sectional view through a `still further modified embodiment of a cartridge case in accordance with the present invention which is inserted into the tail piece of a grenade or mortar shell.

Refeuring now to the drawings wherein like reference numerals are used throughout the various views to designate like parts, the metallic bottom piece is designated in all of the embodiments described herein by reference numeral 1, the outer or external collar thereof by reference numeral 2, the extension thereof provided with beads or reinforcements 3 by reference numeral 4 and the pressedin primer or percussion cap by reference numeral 5.

According to FIGURE l, the propellant charge 7 is accommodated within the plastic cartridge case or cont-ainer 6 consisting of somewhat elastic plastic material. The wall part 8 of the plastic cartridge case or propellant charge container 6 near the ignition vside thereof is smaller in outer diameter than the outer colla-r 2 and comprises a reinforcing shoulder portion and is also reinforced specially on the inside thereof and placed or slipped over the extension 4. The thus obtained tight fit .of the plastic case or container 6 on the bottom piece 1 is able to withstand lat any time an explosive pressure olf the propellant charge, the reinforcements of the wall part 8 and the reinforcements 3 constituting cooperative means. The forwardly disposed cartridge case or container part 9, in contrast thereto, is relatively thin-walled and terminates or ends in a blank or cup 10 open on the front side thereof. The bottom 11 of the cup 10 closes the filling space of the propellant charge at the cartridge case or propellant charge container 6.

The plastic case or container 12 for the booster charge is held at the bottom piece 1 in front of the ignition cap or primer 5v by means of the collar rim 14 thereof inserted into the enlargement 13 `of the buttom piece ignition channel. The internal flange 15 of the enlargement 13 extends over the collar rim 14. The plastic case or container 12 encloses the ignition booster 16. The container or case 12 is closed on the front side thereof and extends into the propellant charge 7. As a result thereof after the initiation of the ignition, the gas pressure becomes so effective in a particularly rapid manner at the rear part of the cartridge case or container 6 within the area of the ignition booster 16 that the tearing-off of the part 9 of the cartridge case or container takes place directly in front of the reinforced part 8 of the container or cartridge case. A pointed cylindrical solid body 3d is indicated in FIG- URE 1 as shell or projectile for which the bottom 11 of the cup 10 serves as abutment and the side walls 17 of the cup 10 as force or clamp fit.

In FIGURE 2 the plastic container or cartridge case of the propellant charge 7 is designated by reference numeral 18. The cartridge case 18 is for the most part constructed as thick-walled body of conically truncated shape and tapered in front thereof whereby the blank or cup 10 is connected `with the truncated conical body 18 at 19. The filling space for the propellant charge 7 extends up to and into the connecting part 19 of the propellent charge container or cartridge case 18 by means of which it is surrounded in a thin-walled manner. The connecting part at 19 thus determines the tearing-off cross section for the cartridge case 18. The projectile of this embodiment is a threaded bolt 31 adapted to be used as fastening element which is held at the threaded part thereof by means of the side walls 17 of the blank or cup 10. The primer or detonator is constructed as rim primer. In case that the caliber of the projectile to be held by the blank or cup does not coincide with the caliber provided at the cup 10, because it is smaller, then the differenence in dimension can be compensated by a fitting ring inserted into the space of the cup or blank 10.

In FIGURE 3 the projectile body 32 is provided rearwardly thereof with the extension 33 which surrounds with play the plastic cartridge case or propellant charge container 6 in a sleeve-like manner. The external bead 34 reinforcing the end part of the plastic cartridge case 6 is formed thereat within the area of the extension 4 of the bottom piece 1. The projectile 32 is held at the cartridge case 6 by means of this external bead 34. The end wall 35 of the plastic cartridge case or propellant charge container 6 is of relatively strong walled construction. An empty space 36 is -left in front of the end wall 35 within the hollow space of the projectile 32. Similar to the cartridge of FIGURE 1 the gas pressure which upon ignition is produced particularly rapidly within the area of the ignition` booster 16 will tear-olf the plastic cartridge case or container 6 directly in front of the external bulge 34.

In FIGURE 4 the tail piece of a grenade or mortar shell, otherwise of conventional construction therefore not shown in detail herein, is designated by reference numeral 44. The tail piece 44 is provided rearwardly with :the guide means 37 and with lateral apertures 38 in front of the guide means 37 for the radial gas discharge which apertures 38 establish a communication with the hollow space 39 of the tail piece 37. The cartridge case or propellant charge container 45 is inserted into the hollow space 39 and is threadably connected with the tail piece 44 by means of the bottom piece 1 by way of the threads 40 thereof. The ignition booster 16 coupled to the bottom piece 1 again extends into the propellant charge 7 and is spatially closely combined with the primer cornposition 41. The forward end wall 42 of the plastic cartridge case 45 is constructed relatively thin-walled and the closed empty space 43 with a predetermined volume is disposed in front thereof. After tripping of the primer at first the end wall 42 tears-off in the direction toward the empty space 43 and immediately following the same gas discharge apertures corresponding to the lateral apertures 38 are punched-out in the side walls of the cartridge case 45 by the gas pressure whereupon the cartridge together with the grenade `or shell is fired out of the barrel thereof by the gas pressure.

While we have shown and described several embodiments in accordance with the present invention, it is understood that'the same is not limited thereto but is susceptible of numerous changes and modifications within the spirit and scope thereof and we therefore do not wish t-o be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

We claim:

1. A cartridge, comprising: a bottom piece supporting primer means and booster means, plastic propellant charge container means forming part of the cartridge case and closed in front thereof, a propellant charge accommodated within said container means, said booster means including further plastic container means extending into said propellant charge, said container means being subject to tearing thereof by explosion of said booster means and said propellant charge, projectile like body means at the front end of said container means, cooperating means to assure tearing of said container means upon ignition of said booster means and said propellant at a predetermined place along the wall cross section of said container means forwardly adjacent said bottom piece, said cooperating means including means tightly securing said bottom piece to the rear end portion of said container means, the portion of said container means forwardly of said plate being adapted to be shot out of the barrel together with the said projectile like body means upon the occurrence of said explosion, and said cooperating means further comprising internal and external reinforcements on said container means, said internal reinforcements being adapted for connection with said bottom piece, said tearing taking place in front yof and adjacent to said reinforcements, said cooperating means further includes external reinforcing means on said container means, said plastic container means being constructed as a cup at the front end thereof, and said projectile like body means being clampingly held at said plastic container means by the side walls of said cup, said external reinforcement means comprising a shouldered part on said rear end portion of said container means.

2. A cartridge, comprising:

a bottom piece supporting primer means and booster means,

plastic propellant charge container means forming part of the cartridge case and closed in front thereof, said booster means being spatially combined with said primer means in a compact manner,

a propellant charge accommodated within said container means, said booster means including further plastic container means extending into said propellant charge,

projectile-like body means at the Ifront end of said container means, and cooperating means including connecting means between said bottom piece and said plastic container means to assure tearing thereof at a predetermined place along the wall cross section thereof so that substantially the entire torn plastic container means is shot out of the barrel together with the projectile-like body means,

said first-mentioned plastic container means being constructed as a cup at the front end thereof, and said projectile-like body means being clampingly held at said plastic container means by the side walls of said cup:

and said first-mentioned plastic container means being provided with internal and external reinforcements near said bottom piece, said internal reinforcements being comprised in said connecting means, said internal and external reinforcements bein-g etfective to cause said tearing to take place in front of and adjacent to said reinforcements.

3. The device of claim 2, wherein said internal reinforcements a-re a plurality of internally extending axially spaced annular beads.

4. The device of claim 2, wherein said further plastic container means has a tubular portion closed at its forward end and an external collar rim at its rearward end; and said bottom piece having an internal flange forward of and axially abutting said external collar rim.

5. The device of claim 2, wherein said external reinforcement means comprises a tubular shouldered part on the rearward end portion of said propellant container means, said shouldered part being of a greater external diameter than the remainder of said propellant container means.

6. The device of claim 5 wherein said bottom piece includes an ex-ternal rearward collar having a greater eX- ternal diameter than said shouldered part, and said bottom piece is constructed of metal.

7. The device of claim 2, wherein said propellant charge container means has a substantially uniform cross-section tubular wall surrounding and coextensive with said propellant charge; said cup side walls are homogeneous, uniform cross-section, forward axial extensions of said tubular wall; said propellant container means includes a transverse plastic wall forming the bottom `of said cup and completely closing the forward end of said tubular wall; and said transverse wall being homogeneously connected with said cup and tubular walls.

8. The device of claim 7, wherein said internal reinforcements are a plurali-ty of internally extending axially spaced annular beads; said external reinforcement means comprises a tubular shouldered part on the rearward end portion of said propellant container means, said shouldered part being of a vgreater external diameter than the remainder of said propellant container means; said bottom piece includes an external rearward collar having a greater external diameter than said shouldered part; said bottom piece is constructed of metal; said further plastic container means has a tubular portion closed at its forward end and an external collar rim at its rearward end; and said bottom -piece having an internal flange forward of and axially abutting said external collar rim.

References Cited bythe Examiner UNITED STATES PATENTS 12/1896 l1/l94l 6/1942 8/1962 9/1963 9/1965 Mohr 102-45 Cole.

Weldin 102-45 De Caro et a1 102-38 X Ciccone et al l02-86-5 X Kinna et al 102-44 FOREIGN PATENTS 2/1961 of 1885 6/1955 12/1961 l/l958 Germany. Great Britain. Great Britain. Great Britain. Italy. 

